Within recent years, telephone sets incorporating push-button arrays, commonly including twelve such push-buttons, have come into widespread use and have largely supplanted the previously common rotary dial-type telephone. The individual pushbuttons comprising such a telephone set array normally project through the cover of the telephone, or a portion of the telephone cover. The remainder of the switching array is contained beneath this outer shell of the telephone set. Such telephone sets are also employed in coin-operated pay stations which are generally located in high volume traffic areas where they are subject to damage from environmental hazards, including especially dust, liquid, and the like which can readily seep through the openings surrounding the individual push-button keys and cause damage, in some cases irreparable damage, to the underlying switching device. In such installations, there is also a great likelihood of damage resulting from vandalism, and a protective cover which is permanently attached, and not easily removed, allowing operation of the push-buttons is very desirable.
While several types of covering elements have been previously proposed for use in connection with push-button type telephones, these have not addressed the foregoing problem of providing a protective envelopment of the push-button array to prevent damage. For example, patents such as U.S. Pat. Nos. 3,739,105; 3,927,282; 4,002,855; and 3,345,769, have been concerned with a variety of problems including arrangements for facilitating actuation of the buttons by varying spacing of the actuating means for the individual push-buttons, or in the case of the U.S. Pat. No. 3,345,769 patent, providing a means for supporting message pads or the like.
Of further interest in connection with the present invention, is the teaching in the aforementioned U.S. Pat. No. 3,739,105 patent, that the push-buttons on the covering device can be formed to provide a width of material which glows in the dark, thereby facilitating use of the telephone in darkened surroundings.
The problem of providing an adaptation enabling use of a push-button telephone under darkened conditions, such as might be encountered in a dimly-lit pay phone station, is indeed a problem which has been occasionally addressed, but never adequately met. Thus, it may be noted that numerous prior art devices extending back many years and directed toward a similar problem in a rotary dial telephone, have considered use of phosphorescent materials in some manner as to enable limited visible under darkened conditions as in the mentioned U.S. Pat. No. 3,739,105 patent.
Pursuant to the foregoing, it may be regarded as an object of the present invention to provide a simple, inexpensive to manufacture, cover for use with a push-button dial telephone or the like, which device acts to effectively seal the push-button array against damage, while at the same time providing no interference with use in actuation of the push-buttons.
A further object of the invention is also to provide a cover which can be permanently attached to the face of a push-button coin-operated telephone and which is relatively vandal-proof.
It is a still further object of the present invention to provide a protective cover of the above character which may further include phosphorescent indicia to enable visibility under reduced light conditions.